$EA ends up holding a list of email addresses (6 of them) in an array. But the only thing that displays in the ListBox is "(Collection)", which is obviously not what is wanted here. I would like for the 6 email addresses to show up in the ListBox, one per line.

I didn't see your post/reply until today. I found the issue though. Turns out just had to make one simple change to line 5 as below:

[System.Array]$EA = $holdval2.EmailAddresses

For some reason, the data type for $EA was being set to ArrayList instead of just Array, and the Load-Listbox function is expecting an object of data type [array]. So once I added the "[System.Array]" right before $EA it all worked perfectly.

By the way, do you know exactly what the difference is between the two data types Array and ArrayList??? and why are there two?